Broan 358 Roof Mount 120-Volt Powered Attic Ventilator, 1000 CFM 4.3 Amps 1000 CFM for up to 1400 square feet of attic space Precision balanced 14-Inch metal blade for maximum air flow and minimum sound level with .050 aluminum dome 23 gage metal flashing - allows for nailing and hot tar application and mesh bird screen Built-in adjustable thermostat - for automatic operation at your chosen temperature level and thermally protected and permanently lubricated motor Mounts easily between rafters - installation template included